A technique for supporting objective analysis of a cause of a traffic accident has been known (for example, JP-A-2017-182490). In a technique described in. JP-A-2017-182490, an accident vehicle and an accident related vehicle are identified based on an accident occurrence time and an accident occurrence position, and operation history information of the identified accident vehicle and the identified accident related vehicle is extracted. Based on the extracted operation history information, driving situations of the accident vehicle and the accident related vehicle before the accident occurs are identified. Then, by comparing the driving situations of the accident vehicle and the accident related vehicle, objective analysis of a cause of the accident is supported.